A new dynamic is emerging in oil pipeline politics – First Nations clashing with First Nations.

On Wednesday, the same day the aboriginal-led Eagle Spirit pipeline proposal announced it secured support – after three years of trying — of every First Nation chief along its route in British Columbia, other First Nations chiefs were meeting in Vancouver to discuss forming a national alliance to fight oil sands pipelines.

Chiefs from Manitoba, Ontario and Quebec appeared before the annual assembly of the Union of B.C. Indian Chiefs and won unanimous backing for a resolution “to develop shared positions and coordinated strategies for addressing climate change and other environmental and cultural impacts of tar sands development.”

The visiting chiefs said they were inspired by their Western Canadian counterparts’ battles against Enbridge Inc.’s Northern Gateway and now want to “extend that wall of opposition out East to stop the TransCanada (Corp.) Energy East tar sands pipeline,” Grand Chief Serge Simon of the Mohawk Council of Kanesatake, a Quebec band, said in a statement.

The clash highlights the difficulties of obtaining “social licence” – a test increasingly demanded by First Nations, but tough to meet given the different interests of the 634 recognized First Nations in the country. It’s also unclear how it squares with the broader “public interest,” which is what regulators were mandated to achieve until the pipeline permitting process became a political football.

So far, only the Eagle Spirit plan, a pipeline between Fort McMurray and Prince Rupert, led by First Nations in B.C. and Alberta and backed by the Aquilini Group, appears to have achieved social licence. Its plan proposes an energy corridor to accommodate both natural gas and bitumen pipelines through northern B.C.

It’s hardly a new concept – politicians and oilpatch leaders in Alberta have floated it for years.